问题描述： 在使用Apache Nifi将JSON消息发布到IBM Websphere MQ时，当尝试覆盖JMS_IBM_*属性时，PublishJMS处理器失败。

解决方法： 要解决这个问题，需要使用自定义的Nifi处理器来处理覆盖JMS_IBM_*属性的需求。下面是一个示例代码，演示如何使用自定义的处理器来替代PublishJMS处理器。

首先，创建一个新的Java类，命名为CustomPublishJMSProcessor。

import org.apache.nifi.annotation.behavior.InputRequirement;
import org.apache.nifi.annotation.behavior.InputRequirement.Requirement;
import org.apache.nifi.annotation.behavior.ReadsAttribute;
import org.apache.nifi.annotation.behavior.ReadsAttributes;
import org.apache.nifi.annotation.behavior.WritesAttribute;
import org.apache.nifi.annotation.behavior.WritesAttributes;
import org.apache.nifi.annotation.documentation.CapabilityDescription;
import org.apache.nifi.annotation.documentation.SeeAlso;
import org.apache.nifi.annotation.documentation.Tags;
import org.apache.nifi.annotation.lifecycle.OnScheduled;
import org.apache.nifi.components.PropertyDescriptor;
import org.apache.nifi.flowfile.FlowFile;
import org.apache.nifi.processor.AbstractProcessor;
import org.apache.nifi.processor.ProcessContext;
import org.apache.nifi.processor.ProcessSession;
import org.apache.nifi.processor.ProcessorInitializationContext;
import org.apache.nifi.processor.Relationship;
import org.apache.nifi.processor.exception.ProcessException;
import org.apache.nifi.processor.util.StandardValidators;
import org.apache.nifi.processor.util.pattern.PutJMS;

import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

@Tags({"example"})
@CapabilityDescription("Example custom PublishJMSProcessor")
@SeeAlso({})
@ReadsAttributes({@ReadsAttribute(attribute = "", description = "")})
@WritesAttributes({@WritesAttribute(attribute = "", description = "")})
@InputRequirement(Requirement.INPUT_REQUIRED)
public class CustomPublishJMSProcessor extends AbstractProcessor {

    public static final PropertyDescriptor DESTINATION = new PropertyDescriptor.Builder()
            .name("Destination")
            .description("The name of the JMS destination")
            .required(true)
            .expressionLanguageSupported(false)
            .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
            .build();

    public static final Relationship SUCCESS = new Relationship.Builder()
            .name("success")
            .description("Success relationship")
            .build();

    public static final Relationship FAILURE = new Relationship.Builder()
            .name("failure")
            .description("Failure relationship")
            .build();

    private Set relationships;
    private List descriptors;

    @Override
    protected void init(final ProcessorInitializationContext context) {
        final Set relationships = new HashSet<>();
        relationships.add(SUCCESS);
        relationships.add(FAILURE);
        this.relationships = Collections.unmodifiableSet(relationships);

        final List descriptors = new ArrayList<>();
        descriptors.add(DESTINATION);
        this.descriptors = Collections.unmodifiableList(descriptors);
    }

    @Override
    public Set getRelationships() {
        return relationships;
    }

    @Override
    public final List getSupportedPropertyDescriptors() {
        return descriptors;
    }

    @OnScheduled
    public void onScheduled(final ProcessContext context) {
        // Initialize connection factory and destination
        ConnectionFactory connectionFactory = // Initialize your connection factory here
        Destination destination = // Initialize your destination here

        // Store the connection factory and destination to the process context
        context.setProperty("connectionFactory", connectionFactory);
        context.setProperty("destination", destination);
    }

    @Override
    public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException {
        FlowFile flowFile = session.get();

        if (flowFile == null) {
            return;
        }

        // Get connection factory and destination from the process context
        ConnectionFactory connectionFactory = context.getProperty("connectionFactory").asControllerService(ConnectionFactory.class);
        Destination destination = context.getProperty("destination").asControllerService(Destination.class);

        try {
            // Create JMS session and message producer
            Session jmsSession = connectionFactory.createConnection().createSession(false, Session.AUTO_ACKNOWLEDGE);
            MessageProducer producer = jmsSession.createProducer(destination);

            // Create JMS message
            Message message = jmsSession.createTextMessage();

            // Set JMS_IBM_* properties
            message.setStringProperty("JMS_IBM_MQMD_ApplIdentity